The ocean has issues: 7 biggest problems facing our seas, and how to fix them

The oceans are among our biggest resource for life on earth, and also our biggest dumping grounds. That kind of paradox could give anyone an identity crisis. We seem to think we can take all the goodies out and put all our garbage in, and then expect them to keep happily ticking away indefinitely. However, while it's true the oceans can provide us with some amazing eco-solutions like alternative energy, they're are undergoing some serious stress factors. Here are the seven biggest problems, plus some light at the end of the tunnel.

1. Overfishing Is Draining the Life From the Water

Overfishing is having some serious impacts on our oceans. Not only does it work towards wiping out a species, but also the other species of marine animals that are dependent upon those fish for survival. It's been shown that overfishing can cause marine animals to starve, since we're taking food from their mouths in too large of numbers for them to be able to get their fill. It is also estimated that most seas already need long term fishing bans if certain species are to recover at all.

There is much to be desired in the ways we fish. First, we humans use some pretty destructive methods in how we pull catches, including bottom trawling which destroys sea floor habitat and scoops up many unwanted fish and animals that are tossed aside. We also pull far too many fish to be sustainable, pushing many species to the point of being listed as threatened and endangered.

Reasons for overfishing are obvious in some ways, in that there are a lot of people who like to eat a lot of fish. The more fish, the more money for the fishermen. However there are other elements at work that promote overfishing that are less obvious, such as promoting the health benefits of one fish over another, or the health of fish oils.

2. The Ocean's Most Important Predators Being Killed...But Just for the Fins

Overfishing is an issue that extends beyond familiar species like bluefin tuna and orange roughy. It's also a serious issue with sharks. Sharks are killed in the tens of millions each year, mainly for their fins. It is a common practice to catch sharks, cut off their fins, and toss them back into the ocean where they are left to die. The fins are sold as an ingredient for soup. And the waste is extraordinary.

Sharks are top-of-the-food-chain predators, which means their reproduction rate is slow. Their numbers don't bounce back easily from overfishing. On top of that, their predator status also helps regulate the numbers of other species. When a major predator is take out of the loop, it's usually the case that species lower on the food chain start to overpopulate their habitat, creating a destructive downward spiral of the ecosystem.

3. Ocean Acidification Sending Us Back 35 Million Years

Ocean acidification is no small issue. The basic science behind acidification is that the ocean absorbs CO2 through natural processes, but at the rate at which we're pumping it into the atmosphere through burning fossil fuels, the ocean's pH balance is dropping to the point where life within the ocean is having trouble coping.

"Ocean acidification is more rapid than ever in the history of the earth and if you look at the pCO2 (partial pressure of carbon dioxide) levels we have reached now, you have to go back 35 million years in time to find the equivalents" said Jelle Bijma, chair of the EuroCLIMATE programme Scientific Committee and a biogeochemist at the Alfred-Wegener-Institute Bremerhaven.

Dead zone research underscores the interconnectedness of our planet. It appears that crop biodiversity on land could help prevent dead zones in the ocean by reducing or eliminating the use of fertilizers and pesticides that run off into the open ocean and are part of the cause of dead zones. Knowing what we dump into the oceans is important in being aware of our role in creating areas of lifelessness in an ecosystem upon which we depend.

Pollution is running rampant in the oceans but one of the scariest pollutants is mercury because, well, it ends up on the dinner table. The worst part is mercury levels in the oceans are predicted to rise. So where does the mercury come from? You can probably guess. Mainly coal plants. In fact, according to the Environmental Protection Agency, coal-fired power plants are the largest industrial source of mercury pollution in the country. And, mercury has already contaminated water bodies in all 50 states, let alone our oceans. The mercury is absorbed by organisms on the bottom of the food chain and as bigger fish eat bigger fish, it works its way back up the food chain right to us, most notably in the form of tuna.

Geoengineering Our Oceans: What We Do and Don't Know About New Technologies

Now for that light at the end of the tunnel, though some may call it a very dim light. the issue of geoengineering, considering the interest we've seen with dumping limestone in the water to balance out the pH levels of the ocean and counter the effects of all that CO2 we pump into the air. Recently we watched as iron filings were dumped into the ocean to see if that'd help suck up some CO2. It didn't. Or rather, it didn't do what we expected it to do.

This is a really controversial area, mainly because we don't know what we don't know. Though that doesn't stop many scientists from saying we have to give it a try.

Research has helped to lay out what some of the risks are in terms of consequences, and in terms of what's just a plain old dumb idea. There are quite a few ideas floating around that claim will save us from ourselves - from ocean iron fertilization to fertilizing trees with nitrogen, from biochar to carbon sinks. But while these ideas hold a seed of promise, they also each hold a sizable nugget of controversy that may or may not keep them from coming seeing the light of day.

Sticking To What We Do Know - Conservation

Of course, good old fashioned conservation efforts will also help us out. Though, looking at the big picture and the extent of the effort required, it might take a lot of gumption to stay optimistic. But optimistic we should be!